Diarrhea: Causes, Symptoms, Management

Introduction

Diarrhea is an increase in the frequency, water content, and volume of bowel movements. In other words, a condition of three or more loose or watery stools per day is called diarrhea. Due to an imbalance in the healthy operation of the small and large intestine’s physiological processes that are responsible for the absorption of various ions, other substrates, and ultimately water, diarrhea causes an increase in the amount of water in stools. It is a typical sign of gastrointestinal diseases brought on by a variety of pathogens, such as viruses, bacteria, and protozoa. Particularly in underdeveloped nations, diarrhea is the second most common cause of morbidity and mortality among children.

• Rotavirus is the most common cause of acute diarrhea, accounting for roughly 40% of cases.
• Acute diarrhea is most commonly caused by rotavirus, which also accounts for 40% of all hospital admissions for diarrhea in children under five worldwide.
• It can result from several conditions, such as gastrointestinal hypermotility, intestinal mucosal fluid secretion problems, and malabsorption disorders.
• Additionally, it might be brought on by an infection, an inflammatory bowel illness, pharmacological side effects, an increase in osmotic loads, radiation, or an increase in intestinal motility.
• Diarrhea occasionally has no identified cause. Infection-related diarrhea often starts 12 hours to 4 days after exposure and goes away in 3 to 7 days.

 Incidence

• The second-most common cause of death in children under the age of five is diarrheal illness. Both prevention and treatment are available.
• Around 525,000 children under five die from diarrhea each year.
• Through clean drinking water, appropriate sanitation, and good hygiene, a major amount of diarrheal disease can be avoided.
• Every year, over 1.7 billion instances of diarrheal illness in children are reported worldwide.
• For children under the age of five, diarrhea is one of the main causes of malnutrition.

Types of Diarrhea

Diarrhea comes in two different clinical forms:

• Temporary (acute) diarrhea: Acute diarrhea lasts one or two days before clearing up. This could be brought on by
  • Consuming contaminated foods or drinks
  • Viral infection
• Prolonged (chronic) diarrhea: Diarrhea that last for several weeks is chronic. This may be caused by medical conditions like
  • Irritable bowel syndrome (IBS)
  • Crohn’s disease
  • Celiac disease can also be to blame. Chronic diarrhea
  • Parasitic infections

Diarrhea can also be categorized based on appearance or color.

• Watery diarrhea: Both acute and chronic diarrheal episodes frequently produce liquid stools.
• Bloody diarrhea: A potentially dangerous illness known as bloody diarrhea occurs when blood is present in loose, watery stools. Bloody diarrhea could be an indication of gastrointestinal bleeding brought on by an illness or accident. Small amounts of blood could potentially be the result of hemorrhoids or rectal tissue irritation.
• Black diarrhea: This condition might be caused by bleeding from the upper digestive tract. Other probable causes of black diarrhea include taking bismuth subsalicylate (Pepto-Bismol), iron supplements, or ingesting blue or black-colored meals or drinks.
• Yellow diarrhea: It could be a sign of liver or gallbladder disease. This is normal for infants.

Causes of Diarrhea

• Viruses: Some viruses that can cause diarrhea are
  • Rotavirus (the most typical cause of severe childhood diarrhea)
  • Norovirus
  • Enteric adenoviruses
  • Astroviruses
  • Cytomegaloviruses
  • Hepatitis virus
• Bacteria: Through contaminated food or drink, bacteria can be exposed leading to diarrhea.
  • Escherichia coli (E. coli)
  • Clostridioides difficile (C. diff.)
  • Campylobacter
  • Salmonella
  • Shigella
• Parasites: Parasites enter the body through contaminated food and water and settle in the digestive tract leading to diarrhea.  
  • Cryptosporidium enteritis
  • Entamoeba histolytica
  • Giardia lamblia 
• Medications: Numerous drugs, including antibiotics, might make you dizzy. While antibiotics are used to treat infections, they also kill beneficial bacteria. As a result, the intestines’ usual bacterial balance is disrupted, which may result in diarrhea or another sickness like C. diff. Other medications that can cause diarrhea include cancer medications and magnesium-containing antacids.
• Lactose intolerance: A sugar called lactose is present in milk and other dairy products. Lactose intolerance causes diarrhea in those who consume dairy products. Lactose intolerance may get worse as you get older because levels of the enzyme that helps digest lactose go down.
• Fructose: Honey and fruits contain naturally occurring sugar fructose. It is occasionally used to sweeten various beverages. Diarrhea can result from fructose.
• Substitute sweeteners: Some otherwise healthy people may get diarrhea after consuming artificial sweeteners like sorbitol, erythritol, and mannitol, which are nonabsorbable sugars used in chewing gum and other sugar-free goods.
• Surgery: Diarrhea can occasionally result after cholecystectomy (the removal of the gallbladder) since the increased bile acid irritates the colon which enters directly into the colon after surgery. 
• Additional stomach issues: The following conditions are more likely associated with chronic diarrhea.
  • Irritable bowel syndrome (IBS)
  • Inflammatory bowel disease (IBD)
  • Crohn’s disease
  • Ulcerative colitis
  • Celiac disease
  • Microscopic colitis
  • Chronic pancreatitis
  • Small intestinal bacterial overgrowth (SIBO)

Risk Factors of Diarrhea

• Poor sanitation (such as not having access to a clean toilet)
• Poor hygiene practices (such as not washing hands)
• Poor availability of clean, safe water.
• Poor nutritional status
• A weakened immune system (caused, for example, by HIV infection or cancer)
• Close contact with someone who is already infected but isn’t yet exhibiting symptoms of infection
• Not having an immunization
• Being infected with a virus, bacteria, or parasite
• Specific medications or dietary supplements
• Changes in your diet or eating habits

Mode of Transmission of Diarrhea 

• The fecal-oral pathway is commonly used to spread diarrheal diseases.
• Poor hygiene can cause an infection to spread from person to person or through tainted food or drinking water. 

Signs and Symptoms of Diarrhea

Symptoms can differ from person to person. Diarrhea symptoms may include:

• Cramps in the abdomen
• Abdominal pain
• Bloating
• Nausea
• Sudden desire to use the restroom
• A fever
• Bloody stools
• Dehydration and fluid loss in the body
• Being unable to regulate your bowel movements and leaking stool

Diarrhea is a major adverse effect of dehydration. These signs include:

• Having dry skin as well as a dry mouth and nostrils (mucous membranes)
• Feeling extremely exhausted
• Feeling as though you might pass out or faint (feeling lightheaded)
• Headaches
• Rapid heartbeat
• A soft spot (sunken fontanelle) on the baby’s head 

Pathophysiology of Diarrhea

• The specific etiology of persistent loose bowels is very wide as there are various causes. Diarrhea can result from any process that makes the stool contain more water.
• When the dynamic and delicately balanced absorption and secretion of water and electrolytes within the gut are lost, diarrhea develops.
• Either osmotic or secretory diarrhea may be present.
• When there are too many osmotically active particles in the lumen, additional fluid passively enters the gut lumen along the osmotic gradient, causing osmotic diarrhea.
• When the intestine mucosa secretes excessive volumes of fluid into the gut lumen, either as a result of a toxin activating a pathway or as a result of innate abnormalities in the enterocytes, the condition is known as secretory diarrhea.

Diagnosis of Diarrhea

History collection

• Any medications they are currently taking
• Their past medical history
• Their travel and family histories

Biochemical test

Biochemical tests usually perform on critically ill or significantly dehydrated patients receiving intravenous (IV) fluids to rule out

• Hypernatremia or hyponatremia (isotonic dehydration is most common)
• Hypokalemia
• Hypocalcemia
• Hypomagnesemia
• Metabolic acidosis
• Elevated levels of urea or blood urea nitrogen (prerenal acute kidney injury)

A complete blood counts

• Anemia may be an indication of malnutrition, bleeding ulcers, or inflammatory bowel disease (IBD).
• Albumin levels will be checked as part of the liver function tests.

Malabsorption tests

• These examine calcium, vitamin B-12, and folate absorption.
• Thyroid function and iron status will also be evaluated.

C-reactive protein and erythrocyte sedimentation rate

• Elevated levels may signify IBD.

Stool tests

• In stool cultures, doctors can find parasites, bacteria, and a few viruses.
• Additionally, white blood cells, tiny blood vessels, and other diagnostic cues can be found in stool samples.

Sigmoidoscopy

• With the help of this test, the interior of a portion of the large intestine is examined. Knowing what is causing the diarrhea is helpful.
• A brief, flexible, lighted tube called a sigmoidoscope is inserted into the intestine.
• The sigmoidoscope helps enlarge the intestine by forcing air into it and facilitating the inside view. If required, a biopsy can be performed.

Colonoscopy

• The entire length of the big intestine is examined during this examination.
• It can assist in looking for any abnormal growths, red or swollen tissue, sores (ulcers), or bleeding.
• A colonoscope (a long, flexible, lighted tube) is inserted into the rectum and advanced into the colon.
• A doctor can use this tube to inspect the lining of your colon and remove tissue.

Fasting tests

• These tests can reveal food intolerance, which is the inability to digest particular meals.
• They are also able to detect food allergies, which are immune system reactions brought on by certain foods.

Treatment/Management of Diarrhea

Rehydration

• Dehydration can be particularly dangerous for young children and the elderly. Rehydrating is essential in every incidence of diarrhea.
• Simply increasing fluid intake can help people replenish lost fluids.
• However, in extreme circumstances, an individual can require intravenous fluids.
• Medically approved combination of a salty and sugary solution called oral rehydration solution (ORS) has greatly decreased childhood mortality from acute infections.
• Supplementing with zinc may help lessen the intensity and length of diarrhea in kids.

(ORS) Oral rehydration solution

In addition to fluids, a patient with diarrhea may require treatment with ORS to replace vital minerals and electrolytes.
In the initial six hours

• Children under the age of six months: 30 to 90 mL (1 to 3 oz) every hour.
• 6–24 months: 90 to 125 mL (3 to 4 ounces) every hour.
• Over two years: 125 to 250 mL (4 to 8 oz) every hour.
• If the baby cannot take ORS from a cup or bottle, try a medicine dropper, a small teaspoon, or frozen pops.
• If the child throws up, stop giving them food and liquids but keep giving them ORS with a spoon.

For at least 6 to 24 hours (recovery stage)

• When the child stops vomiting, it is crucial to give them small, frequent meals while also giving them their regular formula or whole milk.
• Most children can resume their normal diet after 24 to 48 hours.
• Stool production may initially rise (by one or two per day). For stools to fully develop, it can take seven to ten days or more.

Drugs

Anti-diarrheal drugs

• There are additional over-the-counter antidiarrheal drugs available. These include
  • Bismuth subsalicylate (Pepto-Bismol) and
  • Loperamide (Imodium).
• Imodium is an antimotility medication that slows the passage of stools.
• Both adults and children who take Pepto-Bismol experience fewer diarrheal stools.

Antibiotics

• Only bacterial infections that cause diarrhea can be treated with antibiotics.
• Changing to a different medicine may help if a specific substance is the root of the problem.

Diet

The diet recommendations below may aid in preventing diarrhea:

• Consuming clear liquids like electrolyte beverages, water, or fruit juice without added sugar.
• Consuming high-potassium foods and liquids, such as diluted fruit juices, potatoes without the skin, and bananas
• Consuming high-sodium foods and liquids, such as broths, soups, sports drinks, and salted crackers.
• Eating foods high in soluble fiber, such as bananas, oatmeal, and rice, as these helps thicken the stool.

The following foods and drinks could aggravate diarrhea:

• Sugar-free gum, mints, sweet cherries, and prunes
• Medicine and drinks with caffeine
• Fruit juices, grapes, honey, dates, almonds, figs, soft drinks, and prunes contain large levels of fructose
• Dairy goods contain lactose
• Anything that contains artificial sweeteners

Probiotics 

• For the treatment of watery diarrhea with a known or suspected viral cause, several probiotics may be helpful.
• Diarrhea lasts for 1 to 2 days less after taking one sachet or capsule orally every day.
• Some most effective probiotics are
  • Lactobacillus rhamnosus GG
  • Saccharomyces boulardii
  • Bifidobacterium lactis
  • Lactobacillus casei
  • They might aid in the prevention of traveler’s diarrhea, and there is evidence that they might lessen diarrheal disease in children.

Complications of Diarrhea

• Dehydration as well as an electrolyte imbalance
• Reactive arthritis
• Irritable bowel syndrome (IBS)
• Insensitivity to lactose
• Hemolytic-uremic syndrome (HUS)
• Guillain-Barré syndrome (GBS)
• Colitis with hemorrhage
• Toxic megacolon

Prevention of Diarrhea

Maintaining good hand hygiene

• Washing hands thoroughly with soap and water after using the restroom or changing a child’s diaper, before preparing and eating meals, and after handling raw meat or eggs.
• Consistent hygienic checks and adherence to rules for the production and distribution of food and water that are safe.
• Epidemiologic vigilance, locating infection sources (epidemiologic investigations), and mandatory notification of local public health authorities for reportable pathogens.

Get vaccinated

Rotavirus is the most frequent cause of it. The rotavirus vaccination, which is given to children at various dosages within the first year of age, can prevent it.
According to the CDC, babies should receive their rotavirus

• First dose: At two months of age
• Second dose: At four months of age
• Third dose (if necessary): At six months of age 

Proper storage of food

• Food storage best practices include keeping leftovers in the refrigerator.
• Before eating or cooking raw fruits and vegetables, thoroughly wash them and avoid consuming anything that has gone bad.

Pay attention to what you eat and drink

The two main sources of bacteria that cause diarrhea are street food and tap water.

• When dining out, select reputable restaurants, and when traveling, make sure to drink only bottled water.
• Use a water purifier at home.
• Avoid unpasteurized juices and milk.

Breastfeeding

• It has been demonstrated that breastfeeding practices significantly reduce the prevalence of diarrheal sickness in underprivileged communities.
• Studies conducted in a variety of underdeveloped countries have demonstrated that infants who are exclusively breastfed for the first six months of life are better protected against contracting diarrheal illnesses.
• For the first six months, exclusive breastfeeding is currently advised.

Sanitation

• Numerous studies have demonstrated that advancements in water, sanitation, and hygiene (WASH) reduce the likelihood of diarrhea. These enhancements could take the form of sewage connections, high-quality piped water, or the use of water filters.
• The same holds for giving access to better sanitation and reducing open defecation on a community-wide level. This includes using toilets and carrying out every step of the sanitation chain that is associated with them (collecting, moving, disposing of, or recycling human waste).

Prognosis

• The prognosis is favorable for most patients.
• Patients who are elderly, however, run the danger of dying from a serious illness.
• In developed regions, the prognosis is excellent with careful management. However, records show that between the middle of the 1980s and 2006, the mortality rate among US kids attributable to diarrhea increased.
• Black ethnicity, male gender, and low Apgar scores (less than 7) were risk factors for these.
• The leading causes of death are secondary malnutrition and dehydration. For severe dehydration, parenteral fluids should be administered.

Summary

• Three or more loose or watery stools per day are considered to be diarrhea.
• Infections or other reasons can induce diarrhea.
• An individual may get mild to severe diarrhea. In addition to diarrhea, some people also have fever, abdominal pain, or cramps.
• Most of the time, minor diarrhea does not require a visit to the doctor, especially if it starts to get better within 48 hours.
• Infections are typically carried from hand to mouth.
• There are over-the-counter medications to treat diarrhea that are safe if there is no fever and no blood in the stools.
• Drinking fluids containing water, salt, and sugar, such as oral rehydration solution (ORS), is the primary method of treating diarrhea.

References

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